Hi,
I have a G2 Labs BerryNOS DAC (1st gen) and I can report that it is working perfectly with Volumio 1.4 
I tested using Macbook Air running iTunes 11/Airplay over WiFi and also using the Volumio WebUI. No playback issues whatsoever. Music files are 16/44 ALAC rips from CD and are stored on a CIFS NAS (Windows 7 file server).
To configure Volumio to use BerryNOS DAC simply select the Hifiberry I2S profile from the list on the Settings page or follow the instructions in the post below to add a BerryNOS entry to the I2S list.
support-for-berrynos-t1460.html
Regards,
tc-fi